I've been using N-13 for a year or two now and have been very happy with it, but I wanted to sort out the comments on it and allow users to register to comment. I went through the template and added this in, but unfortunately when they login, some random code displays at the top of the article and it doesn't allow them to stay logged in past that page.

Warning: Cannot modify header information - headers already sent by (output started at /home/delamare/public_html/jurassicparkiv.org/index.php:5) in /home/delamare/public_html/jurassicparkiv.org/news/functions.php on line 1438
Warning: Cannot modify header information - headers already sent by (output started at /home/delamare/public_html/jurassicparkiv.org/index.php:5) in /home/delamare/public_html/jurassicparkiv.org/news/functions.php on line 1439
Warning: Cannot modify header information - headers already sent by (output started at /home/delamare/public_html/jurassicparkiv.org/index.php:5) in /home/delamare/public_html/jurassicparkiv.org/news/functions.php on line 1440

This is the code that displays, and it shows at the top of the article once a user has logged in when trying to comment. The problem goes away if you refresh the page, but then they have to login again and the same problem happens. Any ideas why this might be?